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Memo to Steve Shuey 3 June 1 ~ 1998 Spilled ore, waste rock, or other contaminant sources may have been abandoned in the adit at the termination of mining at the site. The next step in the process toward compliance with Rule 3.1.7 at the Bulldog Mine will be to direct the Operator to provide a proposal for characterization ofambient ground water quality related to the 9360 adit water. Rule 3.1.7 provides the Operator with 90 days to respond to the Division's notice that a reasonable potential for ground water contamination exists relative to the plugging of the 9360 adit. However, the Division will direct that the concrete bulkhead valve not be closed until this issue is adequately addressed. This directive will create a situation where the Operator will have to continue to manage the 9360 adit water either through spray evaporation/land application, disposal in the infiltration trench, or discharge to surface water in accordance with the site CDPS permit. Given the poor quality of the 9360 adit water, the Division will not extend 90 day or indefinite approval of land application or infiltration trench disposal without pretreatment of the water. Rather, the Division will enter into discussions with Homestake related to timeframes for establishing pretreatment, but will allow a period of time prior to requiring pretreatment during which Homestake may chazacterize ambient water quality. Unless characterization ofambient ground water quality demonstrates that the 9360 adit water is not degraded by the presence of the adit, or if ambient quality characterization is not completed on a timely basis, the Division will require pretreatment be implemented within a specific number of days to be determined through discussions with the Operator and feasibility considerations. The alternative to pretreatment would be release of the 9360 adit water to the surface water system in accordance with the site discharge permit. On December 8, 1994 the Division sent Homestake notice under Rule 3.1.7(3)(b)(ii)(A) that the flooding of the underground workings at the Bulldog Mine created a potential for degradation of ground water quality. Homestake Mining Company appealed this notice to the Mined Land Reclamation Boazd. Given the nature of [he Boazd's ruling in that matter, the requirements discussed in this memo must be reviewed in the context of the Board Order that was issued. The Boazd's direction to the Division in a hearing held on July 26, 199 was to reconsider any requirement for Homestake to conduct a ground water characterization study at the Bulldog Mine related to flooding of the underground workings. [n making their ruling the Boazd referenced the late stage in the life of the mine and the progress toward reclamation that had been completed prior to the Division's ground water notice to Homestake. The Boazd also raised the concem that simplistic upgradient ground water analyses was not a legitimate means to assess ambient ground water quality in complex geologic settings. Based on direction from the Board, the Division did not pursue any further ground water quality issues at the Bulldog Mine related to the flooding of the underground workings. However, it is the Division's position that the Board's direction provided at the July 26-27, 1995 hearings does not apply to the current situation related to the 9360 adit water. Pertinent history and analysis that leads to this position is provided in the following list. 1. The Division raised the issue of the potential for discharge from the 9360 adit at the time of the initial adequacy review of the 1977 permit application. Homestake's response to the Division's concem was "Once mining operations have terminated, the pumping of water from the mine will cease